Why has my vacuum cleaner lost suction power? Experts reveal 5 common causes and how you can fix them yourself

With all that we rely on our vacuum cleaners for, it's no surprise they occasionally malfunction. A vacuum losing suction power is an all-too-common (and frustrating) issue, but luckily it's a fixable one.

Even the best vacuum cleaners in the world need regular maintenance to keep them at their best. A weakened vacuum is usually a sign of an internal issue, most of which can be fixed easily, either by hand, or with a replacement part.

We spoke to cleaning and appliance experts for the five most common reasons your vacuum cleaner has lost suction power, and what to do next.

Why vacuum cleaners lose suction power

Before delving in to fixes, or cleaning your vacuum cleaner, have you checked if your vacuum is on the right suction setting? Vacuum cleaners have adjustable suction power, and cordless vacuums will often have eco modes to save on energy consumption. Double check yours is on the right mode, then keep reading if that hasn't solved the problem.

1. Full dust containers

Before diving into the more time-consuming reasons why your vacuum's lost suction, make sure to check that the dustbin or bag isn't full. It might sound obvious, but I remember the first time I thought I'd ever broken a vacuum cleaner, and it turned out it was just full.

'Suction power can be reduced by full dust bags or containers. The dust bag can also be torn (or improperly fitted) which will also be a cause of loss of suction power,' says David Miloshev, appliance expert from Fantastic Services.

'If you’ve used your vacuum to pick up really fine dust (inside ducts, drywall, fine sawdust) it will actually plug up the pores in the bag, stopping air from flowing even though the bag isn’t full. Professional cleaners generally change bags as soon as they get half full,' adds David Buckler, president of MaidPro Calgary.

You can stock up on extra vacuum dust bags at Walmart and Amazon.

2. Clogged parts

'The most common reason for a vacuum cleaner to lose suction power is that there's something stuck in the suction hose,' says Martin Orefice, CEO of Rent To Own Labs. 'Generally, you can hear this right away, but it’s the first thing to check,' advises David Buckler.

This clog could be in the wand (if yours is a cordless vacuum), the intake port (the floor head or attachment) or anywhere within the vacuum where air flows. 'Inspect your vacuum cleaner's hose, wand, and brush roll for any items, such as threads, hair or other foreign objects, that can be preventing proper airflow,' explains David Miloshev.

'The brush roll or beater bar may be jammed. In vacuums with rotating brush rolls, hair and string can wrap around the brush, slowing it down. Cutting away debris and ensuring the brush spins freely will restore suction,' says Peter Rania, CEO of Waltham Pest Control Co.

'You'll have to disassemble the vacuum to find the obstruction and pull it out by hand in most cases,' Martin adds.

If yours is a cordless stick this should be an easy task, as you may be able to pull it out yourself or with a long object like a straightened coat hanger or drain snake (like this 35.5-inch Drain Clog Remover from Amazon). Some vacuum cleaners will even come with their own cleaning tools. If the clog is unreachable, you'll have to take the vacuum apart as per the manufacturer's instructions.

When Punteha van Terheyden, Head of Solved at Homes & Gardens had a clog in her Miele vacuum after vacuuming pine leaves from her Christmas tree, she followed the steps from an advisor at the manufacturer and it was a quick way to identify and clear the clog.

She explains, 'If your vacuum has multiple long parts or a hose, and you can separate the components, hold each part vertically, and drop a coin through it. If the coin pops out at the bottom, there isn't an obstruction in that part. If it doesn't come out, you've identified the section that needs clearing. I used a broom handle to loosen the pine leaves in my vacuum hose and was back on my way within five minutes.'

3. Filters need a check

'One of the main and most common reasons vacuum cleaners lose suction is because their filters have been clogged. This restricts the airflow through the appliance and reduces its ability to perform properly,' explains David Mioshev. 'Luckily, this issue is easy to fix by regularly cleaning and replacing the filters. This will include the HEPA filters, foam filters and exhaust filters.'

The filters are responsible for trapping all the particles our vacuums are sucking up, so air is constantly passing through. When they're too clogged, the air isn't as able to flow through the appliance.

'All the air coming into the vacuum must then go out. If your exhaust filters on the back of the vacuum are plugged, it will not be able to pull any more air in. Check and clean your exhaust filters at least yearly,' adds David Buckler.

4. Air leaks

Conversely, vacuums can also suffer from too much air. 'This could mean leaks in the head, hose or body of the vac. Basically, if air can get pulled in anywhere except the business end of the vacuum, it will drop your suction power by a LOT,' explains David Buckler.

'If your vacuum has a hose, plug the end with your hand. For upright vacuums, stuff a sock in the intake. The motor should immediately cycle up louder, and you should feel good suction on your hand.' If it doesn't make this noise, you should be able to hear whereabouts the air is coming in.

'Feel along the hose and body of the vacuum to see if there are any leaks where air is being pulled through. Leaky hoses can be taped (duct tape is your friend) or replaced. Leaky cases are tougher. Try taping cracks, or use an epoxy to seal them,' he adds.

Duct Tape at Amazon is a cheap fix.

5. Worn out or damaged parts

A vacuum cleaner is made of many parts, including a hose, gasket, seals, belts, fan blades, and rotating brushes and all of them can become worn out or damaged over time.

Loose or broken rubber belts:
'If your vacuum is losing suction power slowly over time, rather than all at once, the issue may be a belt that is wearing out,' explains Nick Valentino, VP of Market Operations of Bellhop. 'Rubber belts provide the drive power in most vacuum cleaners, transferring power from the motor to the fan or rotating brush. When these belts start to wear out, they can become slack and lose texture, which makes them less efficient.'

You'll have to take the vacuum apart to access the belt and assess its condition. It is possible to replace it yourself, but if you're not confident then it's probably best to get it professionally repaired.

Damaged seals and gaskets
'The seals and gaskets of your vacuum cleaner can also have gaps or cracks and this can lead to leaks in the airflow system, which will reduce the appliance’s suction power,' says David Miloshev.

'Check for moving parts along the edges of the seals and gaskets while the vacuum is on. If you feel air coming out around these areas or if you notice a significant difference in suction when pressing against them, clean or replace the parts according to the manufacturer's instructions.'

Luckily, 'carefully inspecting seals and gaskets for damage and replacing them is often an inexpensive fix,' says Peter Rania.

Worn fan blade
'Every vacuum has at least one fan blade that spins, creating the suction. After years of sucking up rocks, Lego, thumbtacks, etc., those fan blades get beat up and worn. Depending on your vacuum type, you may be able to replace the fan. You’ll see a major improvement in suction, and it’s generally a cheap repair,' David Buckler shares.

If you find yourself fixing your vacuum cleaner a little too often, or the suction power is never that great, it might be time for an upgrade. Consider one of the best cordless vacuums or best vacuums for pet hair for some tried-and-tested advice.